1. Field of the Invention
The invention relates to a device for influencing a lighting installation.
2. State of the Art
The present type of lighting installation frequently appears in the state of the art and, in a vehicle, serves to turn on and turn off, e.g., the exterior lighting of a vehicle consisting of headlights and tail lights. Because of the risks that arise when operating a vehicle under conditions of poor visibility or in twilight without turning on the lights, it is frequently desirable for the low-beam headlights of a vehicle to be turned on automatically and without the assistance by the vehicle operator.
It already has been proposed for this purpose, in DE 37 37 396 A1 and DE 196 08 184 C2, to employ a sensor device that detects changes in the ambient light and that turns on or turns off a lighting installation as a function of such changes. In this connection, the knowledge is employed that daylight contains wavelengths of light that may be detected unequivocally and which are not present in darkness or in the ambient light, or even in the presence of street lighting. Consequently, an optical filtering device is used in both cases, which, however, always is required in addition to the sensor and which filters the wavelengths of daylight. This occurs either by means of a preceding filtering glass, which, according to DE 37 37 395 A1 is a specialty glass of the Schott company, Mainz, or, according to DE 196 08 184 C2, a UV filter permanently fixed to a brightness sensor or, simply slipped onto the latter or to the holder of same. Alternatively, a corresponding filtering layer may be applied directly to a brightness filter by means of vacuum evaporation, spray-painting or conventional painting. Consequently, each case requires an additional step and an additional filtering device.
As is well known, many vehicle operators have decreased perceptive ability in darkness, which is further decreased by dampness or moisture on the windshield. In this respect, it already has been proposed, in DE-A 41 34 432 and in DE 196 03 663 C1, to control a precipitation sensor as a function of ambient light. At the same time, either a stray light detection device was assigned to an optical precipitation sensor or the precipitation sensor itself was used as a brightness sensor by filtering the signals to detect and evaluate the share of ambient brightness.